diff --git a/test/inhfd/tty.py b/test/inhfd/tty.py
new file mode 100755
index 000000000..a158baef4
--- /dev/null
+++ b/test/inhfd/tty.py
@@ -0,0 +1,17 @@
+import os, pty
+import termios, fcntl
+
+def child_prep(fd):
+	fcntl.ioctl(fd.fileno(), termios.TIOCSCTTY, 1)
+
+def create_fds():
+	(fd1, fd2) = pty.openpty()
+	return (os.fdopen(fd2, "w"), os.fdopen(fd1, "r"))
+
+def filename(pipef):
+	st = os.fstat(pipef.fileno())
+	return 'tty[%x:%x]' % (st.st_rdev, st.st_dev)
+
+def dump_opts(sockf):
+	st = os.fstat(sockf.fileno())
+	return ["--external", 'tty[%x:%x]' % (st.st_rdev, st.st_dev)]
diff --git a/test/inhfd/tty.py.desc b/test/inhfd/tty.py.desc
new file mode 100644
index 000000000..10666c823
--- /dev/null
+++ b/test/inhfd/tty.py.desc
@@ -0,0 +1 @@
+{ 'flavor': 'h' }
diff --git a/test/zdtm.py b/test/zdtm.py
index eb59290a9..89395fd95 100755
--- a/test/zdtm.py
+++ b/test/zdtm.py
@@ -454,6 +454,9 @@ class inhfd_test:
 		self.__peer_pid = os.fork()
 		if self.__peer_pid == 0:
 			os.setsid()
+
+			getattr(self.__fdtyp, "child_prep", lambda fd : None)(peer_file)
+
 			os.close(0)
 			os.close(1)
 			os.close(2)